In recent years, as a variety of electronic equipments become compact, electronic devices to be installed inside the electronic equipments have become more compact and higher in performance. As one of the electronic devices, there is a ceramic electronic device, such as a CR built-in substrate and a multilayer ceramic capacitor, and the ceramic electronic devices have been required to be more compact and higher in performance.
To pursue a more compact ceramic electronic device having a higher capacity, there is a strong demand for making a dielectric layer thinner. Recently, a thickness of a dielectric green sheet composing a dielectric layer has become a several μm or less.
To produce a multilayer ceramic capacitor, an interlayer thickness of a sheet formed with an internal electrode is in a range of about 3 μm to 100 μm based on a desired capacitance required as a capacitor. Also, in a multilayer ceramic capacitor, a part not formed with the internal electrode is formed on an outer part in the stacking direction of the capacitor chip.
In recent years, as electronic equipments become more compact, electronic devices to be used therein have rapidly become more compact. In multilayer electronic devices as typified by a multilayer ceramic capacitor, rapid development has been made on increasing the number of layers to be stacked and attaining a thinner interlayer thickness. To respond to the technical trends, a thickness of a green sheet, which determines the interlayer thickness, has almost become 3 μm or less to 2 μm or less. Therefore, in a production process of a multilayer ceramic capacitor, it is necessary to handle extremely thin green sheets and to design very advanced green sheet properties.
As characteristics required as the properties of such an extremely thin green sheet, sheet strength, flexibility, smoothness, adhesiveness when being stacked, handlability (electrostatic property), etc. may be mentioned, and balance of a higher order is required.
Also, when alternately stacking green sheets and internal electrode layers as in a multilayer ceramic capacitor, the internal electrode layers in a predetermined pattern sandwiched by green sheets are formed with a space (blank pattern) where an electrode is not formed. Due to the blank pattern, there arises a level difference from portions where the internal electrode layer exists, consequently, delamination between sheets and deformation of a stacked body, etc. become problems. To solve the problems, as disclosed in the Japanese Unexamined Patent Publication No. 56-94719, the Japanese Unexamined Patent Publication No. 3-74820, the Japanese Unexamined Patent Publication No. 9-106925 and the Japanese Unexamined Patent Publication No. 2001-237140, a method of forming a pattern layer made by the same dielectric paste as that of the green sheets on the blank pattern portions not formed with the internal electrode has been proposed.
However, in recent years, a thickness of the internal electrode is demanded to be 1 μm or less due to a more compact electronic device with a larger capacity, so that a thickness of the blank pattern is also demanded to be 1 μm or less.
When forming an extremely thin pattern layer made by a dielectric paste on the blank pattern portion not formed with internal electrodes, it is sufficient if a content of ceramic powder is reduced in the dielectric paste. However, in this case, viscosity of the dielectric paste extremely declines, so that there arises a problem that the paste flows out from a mesh of a print plate making and printing in a predetermined pattern becomes impossible. Also, to make up for the decline of the viscosity, it may be considered to increase an amount of an organic binder included in the paste. However, in this case, there is a problem that delamination, etc. arises between sheets when performing binder removal on the stacked body.
Furthermore, in the case of forming an extremely thin blank pattern, when a conventionally general ethyl cellulose based resin is used as the binder resin of the paste, there are also problems that the strength declines and adhesive force declines as the layer becomes thinner as the layer becomes thinner.